Pine wood
| Pine wood | |
|---|---|
 |
|
| Tree species |
Scots pine ( Pinus sylvestris ), Swiss stone pine ( Pinus cembra ), Weymouth pine ( Pinus strobus ) and others |
| origin |
Eurasia, North America |
| Material properties | |
| Bulk density mean | 520 kg / m 3 |
| Raw density limit values | 300-860 kg / m 3 |
| Axial shrinkage | 0.4% |
| Radial shrinkage | 4.0% |
| Tangential shrinkage | 7.7% |
| Flexural strength | 80 N / mm 2 |
| Compressive strength | 45 N / mm 2 |
| tensile strenght | 100 N / mm 2 |
| Thermal conductivity | 0.133 W / (m K) |
| Fuel properties | |
| Calorific value | 4.4 kWh / kg |
As pine wood is wood of pine (genus Pinus ) designated as the BSP. also fir , pine or larch wood to the conifers belongs. In Europe, this name almost exclusively refers to the wood of the Scots pine ( Pinus sylvestris ). Internationally there are a number of other species whose wood is used for different purposes, including the Swiss stone pine ( Pinus cembra ), the Weymouth pine ( Pinus strobus) and the black pine ( P. nigra ), which is increasingly grown due to its insensitivity to air pollution .
Names and meaning
Pine wood is marketed under a number of different names that are also used for the trees themselves; among them are e.g. the names of Scots pine , Scots pine , sand pine , white pine , fir , Forche or Forle . Wood that is sold as Nordic pine or polar pine in Germany, Austria or Switzerland usually comes from Scandinavia , Finland and Russia . Other names related to the origin are Polish pine or East Prussian pine . A trade name for pine wood is also Rotholz , as well as Redwood , Baltic Redwood .
The Scots pine is the second most common forest tree species in Germany and parts of Central Europe after the spruce . In Germany, their area makes up about 27% of the total forest area, while the spruce can be found on about 32% of the forest area. The distribution is very different from region to region and the proportion of pine trees is e.g. in Baden-Württemberg , Saarland and North Rhine-Westphalia around 11 to 15%, while in Mecklenburg-Western Pomerania and Saxony-Anhalt it can be over 50%. In Brandenburg , the spread of the pine with 82% not only determines the landscape, it also represents the "bread tree" of the local forestry. In all of Europe and North Asia, the pine is one of the most important forest trees, with its area of distribution and use over large parts of Europe and Asia's draws.
properties
In the stand, pines grow largely straight with a solid and cylindrical trunk, whereby the growth form can be very dependent on the region and the ecological conditions. Regionally, the strains can accordingly krummschäftig, spirally grown and starkästig be. Under optimal conditions, the branch-free trunk lengths reach up to 20 meters with a total height of the tree of up to 48 meters, the diameter is 0.4 to 0.6 meters, and a maximum of about 1 meter. As a comparatively undemanding species, the pine is very fast-growing and can achieve wood growth of 7.8 m 3 per year; Chopping wood is harvested at around 100 to 120 years of age, high quality wood is more than 160 years old.
In contrast to the spruce and the fir, the core and sapwood areas differ in color very clearly from each other (heartwood tree). The 2 to 10 centimeters thick sapwood has a yellowish to reddish white color, while the heartwood is fresh reddish yellow and darkens to a reddish brown to reddish brown tone. The annual rings are clearly separated from each other and measure an average of around 3 millimeters, although they can vary greatly between one millimeter and almost one centimeter depending on the location. The latewood is significantly darker and red-brown in comparison to the light earlywood. The resin channels are clearly more pronounced than in the spruce or larch and can also be seen macroscopically.
Pine wood has an average bulk density of 520 kg / m 3 with a moisture content of 12–15% and is therefore of medium weight compared to other softwoods. The mechanical properties of the wood are very good compared to those of the spruce, but at the same time the range is very large and depends on the origin and the growth conditions of the pine. The density decreases with increasing annual ring width (and with it a smaller proportion of latewood); the mechanical properties also deteriorate as a result. Good toughness and moderate shrinkage are also very useful properties of wood.
The heartwood of the pine is moderately to less durable against wood-destroying fungi. This means that it can be used untreated for load-bearing components in areas where occasional humidification is possible, but not with contact with the ground or direct weathering. The wood is largely immune to pests such as the house billy and common rodent beetles . In contrast, the sapwood is susceptible to fungal and insect attack; For outdoor use, the wood must be treated accordingly with chemical wood preservatives . Moist sapwood with a moisture content of over 25% is very susceptible to blue stain , which does not cause any change in mechanical properties, but has an optical impact on use and can have an impact on the ability to absorb liquids. In addition, blue-stain fungi are able to damage coatings and thus promote consequential damage.
The processing of the wood by sawing, planing, milling, knives (for the production of veneers) and other techniques is possible without any problems, also the connection with screws and nails as well as with glue is problem-free. Paints, glazes and stains can be used without any effort, but strong resin contents can have a negative effect here.
Scots pine ( Pinus sylvestris )
Swiss stone pine ( Pinus cembra )
White pine ( Pinus strobus )
use
Material use
Pine wood is marketed and used in the form of round, sawn and veneered wood, and it is also used for the production of wood-based materials , especially chipboard with a high proportion of pine wood. Another central use for the wood of the pine and other conifers is the production of paper and pulp, although the pine is not in the bsp. in Germany for ecological reasons dominant sulphite processes can be digested. Due to the longer fibers compared to hardwoods, their fibers become matted more easily and the paper is stronger.
Pine wood is used almost everywhere as construction and construction timber; both in interior construction and in exterior applications. It is used accordingly in house construction for roof structures , for wood paneling, railings, stairs, skeleton structures for walls and ceilings, floors, windows, doors and gates. Impregnated pine wood is used as facade cladding, terrace decking and for other uses as children's play equipment, fences, pergolas and other things in gardening and landscaping. In addition, there are a number of other applications such as masts, posts, piles and other outdoor applications, especially as driven piles in the water, port and mining industries. For less polluted and tram lines are wooden sleepers made of pine and larch wood used.
Furniture making is one of the main areas of application for pine wood; it is used both solid and in the form of wood-based materials as blind wood and main wood for simple furniture, pine wood veneers are also used for the visual design. In the packaging industry, for example Crates, pallets, containers, barrels and other containers as well as wood wool made from pine wood.
Energetic use
In the area of energetic use, pine wood plays a central role with a calorific value of 4.4 kWh / kg or 1,700 kWh / m3 ; both in the form of split logs for domestic fires and in the form of wood chips , wood pellets and briquettes for the corresponding heating systems. As forest and industrial waste wood , it is also used as an energy resource in biomass heating plants and biomass heating power plants.
supporting documents
- ↑ a b c according to DIN 68364 - Characteristic values of wood species - gross density, modulus of elasticity and strength. May 2005.
- ↑ Peter Niemz: Investigations into the thermal conductivity of selected native and foreign wood species . In: Building Physics 29 . tape 29 , no. 4 . Ernst & Sohn Verlag for Architecture and Technical Sciences GmbH & Co.KG, Berlin 2007, p. 311-312 , doi : 10.1002 / bapi.200710040 .
- ^ Herbert Hesmer: Research reports of the state of North Rhine-Westphalia; No. 3211. Westdeutscher Verlag, 1986, ISBN 978-3-531-03211-5 , p. 248.
- ↑ K. Keller, G. Schneider (Ed.): Hagers Handbook of Pharmaceutical Practice. Volume 6: Drugs P-Z Volume II, 5th edition, Springer, 1994, ISBN 978-3-642-63390-4 , p. 180.
- ↑ Durability class 3–4 according to DIN EN 350-2: Durability of wood and wood products - Natural durability of solid wood - Part 2: Guide for the natural durability and impregnability of selected types of wood of particular importance in Europe.
- ↑ according to DIN 68800 part 3
- ↑ Olaf Schmidt, Tobias Huckfeldt: building mushrooms. in: Johann Müller (Ed.): Wood protection in building construction. Basics - wood pests - prevention - control. Fraunhofer IRB Verlag, Stuttgart 2005, ISBN 3-8167-6647-1 , p. 64 f.
literature
- D. Grosser, W. Teetz: Kiefer . In: Local timber (loose-leaf collection) . Information service wood, wood sales fund - sales promotion fund of the German forest and wood industry, 1998, ISSN 0446-2114 .
